Siemens Healthcare Diagnostics Products GmbH, Marburg, Germany.
Clin Chem Lab Med. 2010 Dec;48(12):1739-43. doi: 10.1515/CCLM.2010.339. Epub 2010 Sep 10.
Accurate determination of factor XIII (FXIII) activity is crucial for replacement therapy. FXIII activity is typically determined using a coupled enzymatic reaction that measures nicotinamide adenine dinucleotide hydride (NADH) consumption at 340 nm.
Here, we describe the development of a prototype for a novel FXIII activity assay for detection at 405 nm by replacing NADH with thio-NADH, and the application of FXIII immuno-depleted plasma as a diluent for calibration.
Performance data show up to two-fold lower susceptibility of the prototype assay to interferences from hemolyzed, icteric, and lipemic samples when compared to a NADH assay format. In addition, the use of FXIII immuno-depleted plasma as diluent for calibration improved recovery almost two-fold in the lower measurement range. The novel prototype assay correlates well with a conventional assay (r=0.98, y=0.99·x+2.17% FXIII, n=173).
The described prototype assay has the potential to (a) increase trueness of measurement of low levels of FXIII, (b) improve robustness due to reduction from interferences, and (c) can be used on a broad range of coagulation instruments due to its detection at 405 nm.
准确测定因子 XIII（FXIII）活性对于替代治疗至关重要。FXIII 活性通常通过使用偶联酶反应来确定，该反应测量 340nm 处的烟酰胺腺嘌呤二核苷酸氢（NADH）消耗。
在这里，我们描述了一种新型 FXIII 活性检测的原型的开发，该原型通过用硫代-NADH 取代 NADH，在 405nm 处进行检测，并应用 FXIII 免疫耗尽血浆作为校准的稀释剂。
性能数据表明，与 NADH 测定格式相比，原型测定对溶血、黄疸和脂血样本的干扰的敏感性降低了两倍。此外，使用 FXIII 免疫耗尽血浆作为稀释剂进行校准可将较低测量范围内的回收率提高近两倍。新型原型测定与传统测定方法相关性良好（r=0.98，y=0.99·x+2.17% FXIII，n=173）。
所描述的原型测定法具有以下潜力：（a）提高低水平 FXIII 测量的准确性；（b）由于减少干扰而提高稳健性；（c）由于可以在 405nm 处进行检测，因此可以在广泛的凝血仪器上使用。
